Table 1.
Treatment, mg/kg per d | Striatal volume, mm3 | Density of neurons in the striatum, NV; mean × 106/mm3 ± SEM | Neurons, mean ± SEM | % | n |
---|---|---|---|---|---|
Vehicle | 22.56 ± 0.93 | 0.141 ± 0.003 | 3,179,719 ± 148,757 | 100 | 13 |
3NP 12 + vehicle | 23.05 ± 0.74 | 0.116 ± 0.004214 | 2,682,490 ± 144,728213 | 84 | 15 |
3NP 24 + vehicle | 23.50 ± 0.61 | 0.057 ± 0.010219 | 1,301,823 ± 198,684219 | 41 | 8 |
3NP 12 + CPP 24 | 19.99 ± 0.75** | 0.084 ± 0.006*** | 1,665,659 ± 112,902*** | 52 | 9 |
3NP 12 + MK801 0.3 | 20.33 ± 0.91* | 0.088 ± 0.006*** | 1,766,705 ± 114,380*** | 56 | 6 |
3NP 12 + Memantine 24 | 20.42 ± 0.82* | 0.086 ± 0.007*** | 1,756,120 ± 115,768*** | 55 | 9 |
Vehicle + CPP 24 | 22.35 ± 0.32 | 0.141 ± 0.005 | 3,156,938 ± 127,962 | 99 | 4 |
Vehicle + MK801 0.3 | 22.50 ± 0.63 | 0.141 ± 0.003 | 3,176,258 ± 99,183 | 100 | 6 |
Vehicle + Memantine 24 | 22.41 ± 0.41 | 0.140 ± 0.006 | 3,137,406 ± 135,672 | 99 | 4 |
3NP 12 + NBQX 24 | 22.61 ± 0.35 | 0.136 ± 0.004 | 3,080,253 ± 79,640* | 97 | 6 |
3NP 24 + NBQX 24 | 22.95 ± 0.23 | 0.130 ± 0.009 | 3,000,500 ± 217,863$$$ | 94 | 7 |
Vehicle + NBQX 24 | 22.63 ± 0.74 | 0.140 ± 0.004 | 3,175,564 ± 104,348 | 100 | 6 |
3NP 12 + MPQX 24 | 22.51 ± 0.32 | 0.135 ± 0.004 | 3,036,040 ± 60,090* | 95 | 8 |
3NP 24 + MPQX 24 | 22.09 ± 0.39 | 0.121 ± 0.014 | 2,663,404 ± 277,681$$$ | 84 | 6 |
Vehicle + MPQX 24 | 22.40 ± 0.30 | 0.141 ± 0.006 | 3,152,380 ± 125,392 | 99 | 8 |
Morphometric analyses revealed that striatal volume and Nv of striatal neurons were significantly reduced in rats subjected to parallel treatment with either 3NP, 12 mg/kg per d and CPP, or 3NP, 12 mg/kg per d and MK801, or 3NP, 12 mg/kg per d and memantine over 28 days. The total number of neurons lost in the striatum after combined treatment with 3NP and CPP, or 3NP and MK801, or 3NP and memantine was significantly higher than that in the striatum of rats subjected to 3NP and vehicle. NBQX and MPQX attenuated toxicity of 3NP decreasing loss of striatal volume and numerical density, and reducing loss of neurons in the striatum. The dose of either CPP, MK801, memantine, NBQX, or MPQX chosen for long-term treatment was the maximal tolerated dose that did not induce motor disturbances in rats.
, P < 0.05;
, P < 0.01;
, P < 0.001 vs. vehicle-treated rats; *, P < 0.05; **, P < 0.01; ***, P < 0.001 vs. rats treated with 3NP, 12 mg/kg per d, and vehicle; $$$, P < 0.001 vs. rats treated with 3NP, 24 mg/kg per d, and vehicle (Student's t test).